A lightweight and high-rigidity telescopic boom in which strain during manufacturing is suppressed is disclosed. In a telescopic boom, a plurality of booms forms a telescope structure, and the telescopic boom includes a boom fixing mechanism that fixes a top boom disposed relatively inside at a predetermined position with respect to a first intermediate boom disposed relatively outside. The boom fixing mechanism includes a boom fixing pin that is provided to the top boom and advances and retreats with respect to the first intermediate boom, a fixing boss that is provided to the first intermediate boom and into which the boom fixing pin is inserted and extracted, and a gap maintaining member that is provided to the fixing boss and protrudes outward to maintain a gap between the first intermediate boom and a second intermediate boom disposed further outside.

Telescopic lattice type crane boom for a crane, further comprising a locking system configured to lock at least one telescopic boom section with respect to a base boom section in at least an extended position, wherein said locking system includes a plurality of pins, each pin being configured to extend, in at least the extended position of the boom, at least partly through a corresponding pin receiving aperture provided in one of the base boom section and the at least one telescopic boom section.

This crane is configured by being provided with: a telescopic boom having an inside boom element and an outside boom element that overlap each other in an extendable and contractible manner; an extension/contraction actuator that displaces one boom element among the inside boom element and the outside boom element in the extending and contracting directions; at least one electric drive source provided in the extension/contraction actuator; a first coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the extension/contraction actuator and one of the boom elements; and a second coupling mechanism that operates on the basis of power from the electric drive source and that switches between the coupled state and the uncoupled state of the inside boom element and the outside boom element.

A pin actuator assembly for a telescoping boom includes a locking head having a base, an operating plate operably coupled to the base, one or more cylinder pins and/or one or more section lock arms movable in response to movement of the operating plate relative to the base. The pin actuator assembly also includes an actuator operably coupled to the operating plate and configured to move the operating plate relative to the base. The actuator includes an electric motor and a drive arm. The electric motor is configured to drive the drive arm between an extended drive arm position and a retracted drive arm position. The pin actuator assembly further includes a motion mitigator having a housing, a rod movable relative to the housing and operably coupled to the actuator, a first biasing member coupled between the rod and the housing and a second biasing member coupled between the rod and the housing.

A vehicle crane having a telescoping jib, comprising a basic box with retractable and extendible inner boxes and a securing and locking unit that comprises a first adjusting cylinder and a second adjusting cylinder which are each designed as unilaterally acting hydraulic cylinders with a first spring element and a second spring element as well as a first line and a second line, where the first adjusting cylinder moves locking bolts between operating states of unbolted and bolted and the second adjusting cylinder moves driving bolts between operating states of secured and released. In the event of a malfunction, the first adjusting cylinder moves to the bolted operating state and the second adjusting cylinder moves to the released operating state.

A hoisting crane or multi configurations crane system for use on an offshore vessel, such a vessel and methods for operating are disclosed. The hoisting crane comprises a boom having a proximal portion, an intermediate portion and a distal portion. An extension mechanism is provided that is configured to allow the distal portion to he slid relative to the intermediate portion from a retracted configuration to an extended configuration. In the retracted configuration, the intermediate portion is arranged substantially within the distal portion.

There is provided a crane including: a telescopic boom having an inner boom element and an outer boom element; a telescoping actuator that displaces the inner boom element or the outer boom element in the telescoping direction; a first coupling member that releasably couples the telescoping actuator to one of the boom elements; a second coupling member that releasably couples the pair of boom elements to each other; an electric drive source provided at the telescoping actuator; a first coupling mechanism that displaces the first coupling member or the second coupling member on the basis of motive power of the electric drive source, thereby switching a coupled state and a non-coupled state of the members that are releasably coupled by one of the coupling members; and a position information detection device that detects information relating to the position of one of the coupling members on the basis of output from the electric drive source.

A crane telescope locking device includes a control device which is hydraulically in contact with a telescoping cylinder of a crane telescope and, for the purpose of actuating, with at least one cylinder lock hydraulic cylinder and includes a valve which is open in its inactivated resting state and thus opens a fluidic connection between the telescoping cylinder and the at least one cylinder lock hydraulic cylinder. A telescoping cylinder (6) of a crane includes such a crane telescope locking device.

A hydraulic actuator for a mobile crane, in particular for a locking device of a telescoping device. The hydraulic actuator has a double chamber cylinder with a first cylinder chamber and a second cylinder chamber oriented in an opposite direction to the first cylinder chamber, a first piston rod for the first cylinder chamber, and a second piston rod for the second cylinder chamber. A first restoring spring restores the first piston rod to its main position and a second restoring spring restores the second piston rod to its main position. The main position of the first piston rod is its pushed-in position and the main position of the second piston rod is its extended position.

A locking device for a telescopic boom, in particular of a mobile crane, has an actuator for generating an actuating force, a driver that is reversibly coupled, during a telescoping movement of the telescopic boom, to a locking bolt, which is secured at a boom extension segment of the telescopic boom, and to be moved under the action of the actuating force for adjusting the locking bolt between at least one locking position and a release position. A driver bolt can be moved reversibly by the actuating force between a carry-along position gripping an inner boom extension segment and an empty running position not gripping a boom extension segment. A slotted actuating link is configured for a joint movement of the locking bolt and the driver bolt. A movement plane of the slotted actuating link is oriented perpendicularly to the telescoping direction of the telescopic boom.